Transformer tank structure



March 28, 1939. w. G. JAMES TRANSFORMER TANK STRUCTURE Filed May 17, 1935 Patented Mar. 28, 1939 UNITED STATES PATENT OFFICE TRANSFORMER TANK STRUCTURE of Pennsylvania Application May 17, 1935, Serial No. 21,986

1 Claim.

This invention relates to transformer cases and particularly to sectionalized transformer cases in which it is desired to have an oil or gas-tight joint between the diiferent sections of the case.

An object of this invention is the provision of a simple and eflicient joint construction which is adapted to provide leak proof joints in cases for electrical apparatus.

This invention, together with additional objects and advantages thereof, will be better understood from the following description when taken in conjunction with the accompanying drawing, in which Figure l is a view partly in elevation and partly in section, showing an oil immersed transformer in a sectionalized case, the joints of which embody the features of this invention, and

Fig. 2 is an enlarged vertical sectional View showing the joint between the upper and lower sections of the sectionalized case.

Like reference characters indicate similar parts in the different figures of the drawing.

Referring to the drawing and particularly to Fig. l, a sectionalized transformer case It comprising an upper case section I I and a lower case section I 2 is shown. A cover I3 is provided for the upper case section II and is maintained thereon by suitable means such as bolts 9.

The case ll) contains oil [4 or other suitable insulating medium in which the transformer core I5 is immersed. As is usual in oil immersed transformers, the case H) is large enough to contain the oil necessary for the cooling of transformer core l5, the transformer leads It and the bushings I7.

As illustrated in Fig. 1 and shown in the en; larged vertical sectional View in Fig. 2, a ring flange or stop I8 is provided at a point above the transformer core i5 around the inner wall of the lower case section 12 in order to provide a rest or stop for supporting the upper case section II in its position relative to the lower section 12. The ring flange I8 is securely Welded, as at l9, to the lower section 12 to provide a mechanically strong stop for carrying the weight of upper section H and to support it in assembled position.

A ring flange 20 is provided around the inner wall of the upper section II at its lower edge to cooperate with the flange 18 in positioning the upper section II in assembled relation with the lower section H2. The ring flange 20 is securely welded to the upper section II by welds 2 I.

A plurality of openings 22 are provided in the, ring flanges l8 and 20 for receiving the cap screws 23 for mechanically holding the upper and lower sections in assembled relation. The cap screws 23 are so spaced around the ring flanges as to withstand the mechanical stresses encountered in moving or lifting the case. The gasket 25 is provided between the ring flanges l8 and 2@ for shop testing purposes and oil and gas tight shipment.

In order to assist in positioning the upper section I l and to prevent the crushing of gasket 24, a bead stop 25 is provided on the ring flange l8.

As is evident from the drawing, the upper and lower sections are assembled in telescopic relation with the upper section II being of smaller diameter than the lower section l2 and fitting therein and being supported by the ring flange I8 of the lower section. When the sections are thus assembled, the upper end of the lower section l2 extends upwardly to a point above the joint formed by the flanges l8 and 20. In this particular embodiment, the sections II and I2 are loosely fitted together in telescopic relation. When thus assembled the upper edge of the lower section !2 is forced into contact with the upper section II and is secured thereto by a weld 26. As will be understood, the case sections II and I2 may be of such a size that when assembled they will be in close contact with each other. When thus assembled, it is not necessary to deform the upper edge of the lower section. The weld 26 unites the lower section and. the upper section and provides a leak proof joint therebetween.

In order to test the joints between the upper and lower sections, a pipe plug 21 is provided at some convenient point between the ring flange l8 and the upper edge of the lower section l2. As will be evident to those skilled in the art, the pipe plug 21 may be removed after the case is assembled and the joints are welded so that com pressed air or some other suitable medium can be applied to test the joints for leaks. If a leak is discovered, it can be easily stopped by welding at the point of the leak. After the pressure testing is completed, the pipe plug 21 is replaced in the opening providing a. closed and leak proof sectionalized case.

From the foregoing description, it is evident that this invention provides a sectionalized case which is adapted to be shipped in dismantled form with the transformer in the lower case section and which is adapted to be easily assembled in the field. Further, it is evident that this invention provides a simple and efficient joint between the assembled sections so that when correctly assembled and welded, as hereinbefore set forth, a leak proof case results.

It is, of course, to be understood that although this invention has been shown and described with reference to certain specific embodiments thereof, many modifications are possible, and it is, therefore, not to be restricted except insofar as is necessitated by the prior art and the scope of the appended claim.

I claim as my invention:

A joint structure for use in a vertically ex tending sectionalized case having a lower section of major diameter and an upper section of minor diameter comprising, means disposed around the lower section and below its upper edge for supporting the upper section in telescopic relation,

said means comprising a horizontal flange projecting inwardly from the internal surface of the lower section, means comprising another inwardly extending horizontal flange disposed around the upper section at its lower edge to cooperate with the flange of the lower section in positioning the sections in assembled relation, the lower section extending upwardly beyond and external of the lower edge of the upper section, the upper edge of the lower section of major diameter being forced into contact with the external surface of upper section of minor diameter, and a weld for uniting the contacting upper edge of the lower section to the external surface of the upper section to provide a leakproof joint therebetween.

WILLIAM G. JAMES. 

